A hydraulic control circuit operable to selectively hydraulically link first and second hydraulic actuators and to bypass that hydraulic link.

An example valve includes a valve piston configured to block fluid flow from a first port of the valve to a second port of the valve when the valve is in a closed position; a forward flow spring applying a first biasing force on the valve piston in a distal direction; a reverse flow spring applying a second biasing force on the valve piston in a proximal direction; and a pressure setting spring applying a third biasing force on a check element in the distal direction, wherein fluid from the first port applies a fluid force on the check element in the proximal direction, and fluid from a pilot port applies a respective fluid force on the check element in the distal direction.

An example valve includes a housing, a sleeve disposed within the housing and having a first end and a second end opposite the first end, and the sleeve includes a plurality of sleeve protrusions at the first end and a plurality of fluid flow channels are formed between adjacent sleeve protrusions, a seal carrier disposed within the sleeve and having a carrier protrusion that extends from the second end of the sleeve and abuts against an interior surface of the housing, and an end cap mounted to the housing such that the plurality of sleeve protrusions abut against the end cap.

A valve structure (1) for driving reversible ploughs (40), comprising a first port (3) adapted to be in fluid communication with a pump (P) in a first configuration of the plough (40) and adapted to be in fluid communication with a tank (T) in a second reversed configuration of the plough (40), and a second port (4) adapted to be in fluid communication with the tank (T) in the first configuration of the plough (40) and adapted to be in fluid communication with the pump (P) in the second reversed configuration of the plough (40), a body (2) which includes a first seat (5) and a second seat (6), the seats housing respective moving spools (13, 14), a first interconnection port (7a) for the connection of the valve structure (1) to a first chamber (10a) of a first hydraulic cylinder (10) for longitudinally aligning the plough (40), and a second interconnection port (7b) for the connection to a second chamber (10b) of the first hydraulic cylinder (10), a third interconnection port (8a) for the connection of the valve structure (1) to a first chamber (12a) of a second hydraulic cylinder (12) for reversing the plough (40), and a fourth interconnection port (8b) for the connection to a second chamber (12b) of the second hydraulic cylinder (12). The valve structure (1) comprises hydraulic components configured to control the relative displacement of the spools (13, 14) to automatically control the movement of the cylinders (10, 12). A check valve (31) enables the fluid to flow in the second reversed configuration of the plough (40).

A hydraulic system for an air cart includes a primary hydraulic assembly and a secondary hydraulic assembly. The hydraulic system also includes a first valve configured to block a flow of a hydraulic fluid flowing in a first direction from the primary hydraulic assembly and a second valve configured to block a flow of the hydraulic fluid flowing in a second direction from the secondary hydraulic assembly.

A hydraulic control circuit operable to selectively hydraulically link first and second hydraulic actuators and to bypass that hydraulic link.

An actuation chamber (2) provided in a housing (1) is communicatively connected to a supply and discharge port (6) via a pressurized oil supply and discharge passage (7). A valve case (11) of a sequence valve (10) is attached to an attachment hole (8) provided at an intermediate portion of the supply and discharge passage (7). A valve seat (25) is provided in a cylindrical hole (20) provided in the valve case (11). A valve member (26) is biased leftward toward the valve seat (25) by a pressure-setting spring (31). When pressure of pressurized oil supplied to a first portion of the supply and discharge passage (7) which is close to the supply and discharge port (6) exceeds a set pressure, the pressurized oil moves the valve member (26) rightward for valve opening, against the pressure-setting spring (31).

A valve structure (1) for driving reversible ploughs (40), comprising a first port (3) adapted to be in fluid communication with a pump (P) in a first configuration of the plough (40) and adapted to be in fluid communication with a tank (T) in a second reversed configuration of the plough (40), and a second port (4) adapted to be in fluid communication with the tank (T) in the first configuration of the plough (40) and adapted to be in fluid communication with the pump (P) in the second reversed configuration of the plough (40), a body (2) which includes a first seat (5) and a second seat (6), the seats housing respective moving spools (13, 14), a first interconnection port (7a) for the connection of the valve structure (1) to a first chamber (10a) of a first hydraulic cylinder (10) for longitudinally aligning the plough (40), and a second interconnection port (7b) for the connection to a second chamber (10b) of the first hydraulic cylinder (10), a third interconnection port (8a) for the connection of the valve structure (1) to a first chamber (12a) of a second hydraulic cylinder (12) for reversing the plough (40), and a fourth interconnection port (8b) for the connection to a second chamber (12b) of the second hydraulic cylinder (12). The valve structure (1) comprises hydraulic components configured to control the relative displacement of the spools (13, 14) to automatically control the movement of the cylinders (10, 12). A check valve (31) enables the fluid to flow in the second reversed configuration of the plough (40).

A wire pulling assembly for pulling a wire carrying tooling through an underground environment. The pulling assembly includes a cyclical vise carried by one or more hydraulic cylinders attached to a frame. The cylinders have a pulling stroke and a retraction stroke. A powered reel is used to store the wire as it is removed from the ground. During a pulling stroke, the reel is hydraulically isolated such that cable is stripped from the reel with tension maintained in the cable. During a retraction stroke, a motor turns the reel to load excess cable onto the reel.

An example valve includes a housing, a sleeve disposed within the housing and having a first end and a second end opposite the first end, and the sleeve includes a plurality of sleeve protrusions at the first end and a plurality of fluid flow channels are formed between adjacent sleeve protrusions, a seal carrier disposed within the sleeve and having a carrier protrusion that extends from the second end of the sleeve and abuts against an interior surface of the housing, and an end cap mounted to the housing such that the plurality of sleeve protrusions abut against the end cap.